diff --git a/extra/io/files/unique/backend/backend.factor b/basis/io/files/unique/backend/backend.factor
similarity index 100%
rename from extra/io/files/unique/backend/backend.factor
rename to basis/io/files/unique/backend/backend.factor
diff --git a/extra/io/files/unique/unique-docs.factor b/basis/io/files/unique/unique-docs.factor
similarity index 100%
rename from extra/io/files/unique/unique-docs.factor
rename to basis/io/files/unique/unique-docs.factor
diff --git a/extra/io/files/unique/unique-tests.factor b/basis/io/files/unique/unique-tests.factor
similarity index 100%
rename from extra/io/files/unique/unique-tests.factor
rename to basis/io/files/unique/unique-tests.factor
diff --git a/extra/io/files/unique/unique.factor b/basis/io/files/unique/unique.factor
similarity index 91%
rename from extra/io/files/unique/unique.factor
rename to basis/io/files/unique/unique.factor
index 3a6c556846..74100c7dc7 100644
--- a/extra/io/files/unique/unique.factor
+++ b/basis/io/files/unique/unique.factor
@@ -1,7 +1,7 @@
 ! Copyright (C) 2008 Doug Coleman.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: kernel math math.bitwise combinators.lib math.parser
-random sequences sequences.lib continuations namespaces
+USING: kernel math math.bitwise math.parser
+random sequences continuations namespaces
 io.files io arrays io.files.unique.backend system
 combinators vocabs.loader fry ;
 IN: io.files.unique